Proliferation and directed migration of vascular smooth muscle cells are important vascular occlusive components in such processes as hypertension-induced vascular remodeling, vascular restenosis, and atherosclerosis (Gibbons, G. H.; Dzau, V. J.; NEJM, 1994; 330: 1431). The overall disease process is referred to as hyperproliferative vascular disease based on the etiology of the disease process. Vascular occlusion is preceded by stenosis resulting from intimal smooth muscle cell hyperplasia (Clowes, A. W.; Reidy, M. A.; J. Vasc. Surg., 1991, 13: 885). The underlying cause of intimal smooth muscle cell hyperplasia is vascular smooth muscle cell injury leading to disruption of the endothelium and extracellular matrix (Schwartz, S. M., Human Pathology, 1987; 18: 240; Fingerle, J., Arteriosclerosis, 1990; 10: 1082). Normally, the cells of the arterial wall are under close negative control and in a low basal proliferating state or in a quiescent non-proliferating state. Following vascular injury, the release of growth factors and cytokines result in smooth muscle cell proliferation and migration (Fagin, J. A.; Forrester, J. S., Trends in Cardiovascular Med., 1992; 2; 90.; Shiratani, M.; Yui, Y.; Kawai, C., Endothelium, 1993; 1: 5).
Vascular injury leading to intimal hyperplasia can be induced immunologically or by invasive cardiovascular procedures. Atherosclerosis is a common form of biologically mediated vascular injury progressing to stenosis. Abnormal proliferation of vascular smooth muscle cells is a feature of atherosclerotic plaques responsible for obstructive neo-intimal lesions at the site of intimal damage (Ross, R., Nature, 1993: 362; 801; Cascells, W., Circulation, 1992; 86: 723). Mechanical injury leading to intimal hyperplasia can occur following angioplasty procedures, organ transplant surgery and other vascular invasive procedures that disrupt vascular integrity (Clowes, A. W.; Reidy, M. A., J. Vase. Surg., 1991; 13: 885; Isik, F. F.; McDonald, T. O.; Ferguson, M.; Yanaka, E., Am. J. Pathol., 1992; 141: 1139).
Percutaneous transluminal coronary angioplasty has achieved wide acceptance for the treatment of coronary artery stenosis. In this procedure the endothelium is damaged and exposed to a variety of chemoattractants and mitogens which are either blood-home or are released at the site of injury. Among these agents, platelet-derived growth factor (PDGF) is thought to play a significant role in the process of smooth muscle cell proliferation and chemotaxis (Reidy, M. A.; Fingerle, J.; Lindner, V.; Circulation, 1993:86 (suppl III): III-43.; Ferns, G. A. A.; Raines, E. W.; Sprugel, K. H.; Montani, A. S.; Reidy, M. A.; Ross, R.; Science, 1991; 253: 1129.; Jawien, A., et al., J. Clin. Invest., 1992; 89: 507; Nabel, E. G., et al., J. Clin. Invest., 1993; 91: 1822). Within 3 to 6 months after angioplasty, a significant reduction in blood flow occurs in approximately 30-40% of patients as a result of restenosis caused by response to vascular injury during this procedure. These patients then require a second interventional procedure (Pepine, C., Circulation, 1990; 81: 1753.; Hardoff, R. J., J. Am. Coll. Cardiol., 1990; 15: 1486). Accordingly, agents that limit the restenosis process would be of significant benefit. Agents that inhibit vascular smooth muscle cell proliferation, particularly PDGF-stimulated proliferation, would be useful in the treatment of vascular hyperproliferative disorders (Molloy, C. J., Drug Dev. Res., 1993; 29: 148.; Newby, A. C.; George, S. J., Cardiovasc. Res., 1993; 27:1173).
U.S. Pat. No. 5,387,600, discloses 2-alkyl or heterocyclyl-benzimidazoles of formula I as ACAT inhibitors: ##STR2##
U.S. Pat. No. 5,128,359 discloses 1-benzylbenzimidazol-2-alkanoic acid derivatives for treatment of atherosclerosis.
U.S. Pat. No. 4,814,329 discloses 2-thiobenzimidazoles of following formula II as anti-hyperlipidemic agents, where R is C.sub.1 -C.sub.4 alkyl and C.sub.2 -C.sub.4 hydroxyalkyl: ##STR3##
DE 4212748, discloses N-biphenymethyl benzimidazoles as AII antagonists.